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Cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) is a coinhibitory receptor that plays an essential role in maintaining immune system homeostasis by suppressing T-cell activation. We report a sporadic case of CTLA4 haploinsufficiency in a patient with Epstein–Barr virus-positive diffuse large B-cell lymphoma and subsequent benign lymphadenopathy. A missense mutation in exon 2 of the CTLA4 gene (c.251T>C, p.V84A) was found in the patient’s peripheral blood and buccal cell DNA, but not in her parents’ DNA. CTLA4 expression decreased in the peripheral regulatory T cells upon stimulation, whereas CTLA4 and PD-1-positive T cell subsets increased, possibly to compensate for the defective CTLA4 function. This case suggests that some adult lymphoma patients with no remarkable medical history have primary immune disorder. As immune-targeted therapies are now widely used for the treatment of malignancies, it is increasingly important to recognize the underlying primary immune disorders to properly manage the disease and avoid unexpected complications of immunotherapies.  相似文献   
23.
Hepatitis C virus (HCV) infection is associated with lymphoproliferative disorders. HCV infection of B cells is a predictive factor for lymphoproliferative disorders in patients with chronic hepatitis C, although its molecular mechanisms remain unknown. Epstein-Barr virus (EBV) is a B cell-tropic virus with the potential to cause lymphoproliferative disorders, and its reactivation is induced by several viruses and cytokines. The possibility that HCV infection triggers reactivation of EBV and induces lymphoproliferative disorders were investigated. Expression of EBV mRNAs was analyzed by RT-PCR in patients infected with HCV and control subjects, and correlations between reactivation of EBV and markers for lymphoproliferative disorders were investigated. BZLF1 mRNA, a starter molecule of reactivation, was detected in peripheral blood mononuclear cells from 12 of 52 (23%), patients infected with HCV and the frequency was higher than in healthy subjects [3 of 43 (9%), P = 0.032]. But the presence of the BZLF1 mRNA was not associated with an abnormality of markers for lymphoproliferative disorders. This study on BZLF1 mRNA expression among lymphoid cell subsets showed that reactivation of EBV was observed specifically in B cells. The BZLF1 mRNA disappeared following anti-viral therapy and remained negative after eradication of HCV in patients with a sustained viral response, while the EBER1 RNA, a marker for persistence of EBV, was detected throughout the therapy. Infection with HCV induces reactivation of EBV in B cells, but this reactivation was not associated directly with lymphoproliferative disorders triggered by HCV.  相似文献   
24.
Yorifuji T, Fujimaru R, Hosokawa Y, Tamagawa N, Shiozaki M, Aizu K, Jinno K, Maruo Y, Nagasaka H, Tajima T, Kobayashi K, Urakami T. Comprehensive molecular analysis of Japanese patients with pediatric‐onset MODY‐type diabetes mellitus. Background: In Asians, mutations in the known maturity‐onset diabetes of the young (MODY) genes have been identified in only <15% of patients. These results were obtained mostly through studies on adult patients. Objective: To investigate the molecular basis of Japanese patients with pediatric‐onset MODY‐type diabetes. Subjects: Eighty Japanese patients with pediatric‐onset MODY‐type diabetes. Methods: Mitochondrial 3243A>G mutation was first tested by the polymerase chain reaction restriction fragment length polymorphism analysis for maternally inherited families. Then, all coding exons and exon–intron boundaries of the HNF1A, HNF1B, GCK, and HNF4A genes were amplified from genomic DNA and directly sequenced. Multiplex ligation‐dependent probe amplification analysis was also performed to detect whole‐exon deletions. Results: After excluding one patient with a mitochondrial 3243A>G, mutations were identified in 38 (48.1%) patients; 18 had GCK mutations, 11 had HNF1A mutations, 3 had HNF4A mutations, and 6 had HNF1B mutations. In patients aged <8 yr, mutations were detected mostly in GCK at a higher frequency (63.6%). In patients >9 yr of age, mutations were identified less frequently (45.1%), with HNF1A mutations being the most frequent. A large fraction of mutation‐negative patients showed elevated homeostasis model assessment (HOMA) insulin‐resistance and normal HOMA‐β indices. Most of the HNF1B mutations were large deletions, and, interestingly, renal cysts were undetectable in two patients with whole‐gene deletion of HNF1B. Conclusion: In Japanese patients with pediatric‐onset MODY‐type diabetes, mutations in known genes were identified at a much higher frequency than previously reported for adult Asians. A fraction of mutation‐negative patients presented with insulin‐resistance and normal insulin‐secretory capacities resembling early‐onset type 2 diabetes.  相似文献   
25.
The purpose of the present paper was to examine the level of apoptosis and the relationships among apoptosis, apoptosis-associated proteins, and proliferating potential in lymphoma tissues to clarify the characteristics of apoptosis in diffuse large B-cell lymphomas (DLBCL) of the central nervous system (CNS). The formalin-fixed, paraffin-embedded tissues of CNS and non-CNS DLBCL (20 cases each) were studied by terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) and immunohistochemistry, using antibodies against single-stranded DNA (ssDNA), cleaved caspase-3, bcl-2, bax, p53, Fas and Ki-67. The cleaved caspase-3 immunohistochemistry detected apoptosis of the lymphoma cells most sensitively compared to TUNEL and ssDNA immunohistochemistry. High expression (grade + + or + + +) of cleaved caspase-3 was found more frequently in CNS DLBCL (11 cases, 55%) than non-CNS DLBCL (three cases, 15%; P = 0.009). Bax-positivity of lymphoma cells was increased in six cases of CNS DLBCL, which also showed high positivity of cleaved caspase-3. There was no significant correlation between the cleaved caspase-3-positivity and the Ki-67 positivity. The present study indicates that the number of apoptotic cells and expression level of cleaved caspase-3 were significantly higher in CNS DLBCL than non-CNS DLBCL, and that the correlation of bax and cleaved caspase-3 expression was often present in CNS DLBCL.  相似文献   
26.
PurposeThis study determined the effect of laser‐assisted hatching on the clinical and neonatal outcomes of single vitrified blastocyst transfer.MethodsFrom June 2014 to March 2018, 289 matched pairs after propensity score matching were analyzed. During the blastocyst warming procedure, a small section of the zona pellucida area in the empty perivitelline space was sliced off using multiple laser beams. The clinical and neonatal outcomes of the laser‐treated group and non‐treatment control were analyzed.ResultsIn the laser‐assisted hatching group, significantly higher rates of clinical pregnancy (40.8% vs 29.4%, P < .01) and live delivery (34.3% vs 22.5%, P < .01) were observed compared to the control group. Other variables such as the average gestational weeks, the sex of the baby, birthweight, or congenital malformations were found to have no significant differences in neonatal outcomes. Moreover, all babies were singleton live births.ConclusionsSingle vitrified blastocyst transfer treated with laser‐assisted hatching increases the live birth rate and has no adverse effects on neonatal outcomes.  相似文献   
27.
A case of gastric undifferentiated carcinoma with diffuse c-kit overexpression and focal neuroendocrine differentiation is described. A 76-year-old man presented appetite loss for 1 month. Gastric endoscopy showed an exophytic huge nodular mass with central ulceration at the gastric prepylorus. Distal gastrectomy was performed with lymph node dissection. Histology indicated anaplastic medium- to large-sized round tumor cells in discohesive sheets. Adenocarcinomatous areas forming tubular glands or with intracytoplasmic mucin on PAS and Alcian-blue staining were not found in any sections. Immunohistochemistry showed that the tumor cells were diffusely positive for cytokeratin, vimentin, c-kit and focally positive for chromogranin A and synaptophysin.  相似文献   
28.
BackgroundPerforming total hip arthroplasty (THA) as early as possible is recommended for rapidly destructive coxarthrosis (RDC) as it causes pain that becomes progressively more severe. However, acetabular bone loss remains an issue in THA. Special devices, such as a Kerboull-type plate, may be used for acetabular bone defects, but the procedure is highly invasive and often the patients are elderly, further complicating matters. We retrospectively investigated the clinical and radiographic results of THA using conventional hydroxyapatite-coated cementless cup in RDC.MethodsA total of 32 patients (35 hips) with RDC were enrolled in the study with a minimum 10-year follow-up. All THAs were performed using conventional hydroxyapatite-coated cementless cup. All patients were evaluated clinically according to the Harris hip score (HHS). Acetabular bone deficiency was classified according to the American Academy of Orthopaedic Surgeons (AAOS) classification.ResultsEleven hips (31%) were AAOS type III, and none were type IV. Total HHS significantly improved from 36.5 to 79.4 (p < 0.01). Two cups exhibited loosening. The overall implant-associated survival rate after 10 years was 91.4%.ConclusionsClinical results of THA using conventional cementless implants for patients with RDC were acceptable. Thus, THA using conventional cementless implant is an effective and safe surgery for patients with RDC, minimizing surgical stress.  相似文献   
29.
It is important to understand anatomical feature of the distal femoral condyle for treatment of osteoarthritic knees. Detailed measurement of the femoral condyle geometry, however, has not been available in osteoarthritic knees including valgus deformity. This study evaluated femoral condyle geometry in 30 normal knees, 30 osteoarthritic knees with varus deformity, and 30 osteoarthritic knees with valgus deformity using radiographs and magnetic resonance imaging (MRI). In radiographic analysis in the coronal plane, the femoral joint angle (lateral angle between the femoral anatomic axis and a tangent to femoral condyles) was 83.3 degrees in the normal knees, 83.8 degrees in the varus knees, and 80.7 degrees in the valgus knees. In MRI analysis in the axial plane, the posterior condylar tangent showed 6.4 degrees of internal rotation relative to the transepicondylar axis in the normal knees, 6.1 degrees in the varus knees, and 11.5 degrees in the valgus knees. These results suggested that there was no hypoplasia of the medial condyle in the varus knees, but the lateral condyle in the valgus knees was severely distorted. Surgeons should take this deformity of the lateral femoral condyle into account when total knee arthroplasty is performed for a valgus knee.  相似文献   
30.
The purpose of this study was to determine the incidence of heterotopic ossifications (HOs) after total hip arthroplasty in Japanese patients and the predisposing factors associated with this condition. One thousand hips of 885 patients undergoing cementless total hip arthroplasties were examined with respect to the incidence and severity of HO; the data analysis was conducted by using the univariate and multivariate methods. The overall incidence of HO was 5.2%, with severe HO in 0.9% of the patients. A significant increase in the frequency of HO was observed in patients with ankylosed hips (odds ratio, 11.1; 95% confidence interval, 2.5-49.9), hypertrophic osteoarthritis (odds ratio, 2.7; 95% confidence interval, 1.2-5.9), and with a particular type of prosthesis used (ceramic-on-ceramic vs ceramic-on-polyethylene) (odds ratio, 2.5; 95% confidence interval, 1.3-4.8).  相似文献   
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